A semiconductor manufacturing apparatus includes a chamber that includes a station in which a substrate is provided, a substrate holder that is in the station and receives the substrate, and lower showerheads below the substrate holder, the lower showerheads including an isotropic showerhead having first nozzle holes that isotropically provide a first reaction gas on a bottom surface of the substrate, and a striped showerhead having striped nozzle regions and striped blank regions between the striped nozzle regions, the striped nozzle regions having second nozzle holes that non-isotropically provide a second reaction gas on the bottom surface of the substrate.